Hi everyone. I am coding a personal project for fpga which will be like a computer that never existed. I'm having some trouble with the sdcard io.
Using the code from the original MiST project doesn't seem to work for accessing an sd card.
Could someone please explain how to use the interface properly to read sd card files if possible a tutorial like the original MiST project had.
I am using the petite fat file system in the software side of things. is this alright because i'm thinking that the actual sdcard is formatted for linux.
Any help would be excellent.
There are three major ways to handle the files. You can use the F and when someone chooses a file from the unix side of the MiSTer it will present it on the ioctl_addr and ioctl_data with ioctl_download set. it will also use the index to tell you which F if you have multiple it is for. The rom will also appear on these with a different index.
You can also mount a file using S - this can be a virtual disk, or a virtual filesystem image. I am not as familiar with the S - but you can look at the Scsi interface in the Mac, or some of the other cores. I think is uses sd_rd, etc.
Finally, there is a MiST compatible SD card reader interface. This should be the last resort, since it requires the SD card to be plugged into the I/O card. I feel like it will probably go away. Take a look at the Atari5200 for some sample code.